Setup RTC DS1307/DS3231 on Odroid-C4

[mbonamusa]

Hi,
RTC_Shield is out of stsock, so I want to use an RTC DS1307/DS3221 based RTC on odroid C4. Is it possible?
How can I setup these RTC on Odroid-C4?

[joerg]

What is the OS you are running? On Linux you must check if the kernel has rtc_ds1307 kernel module. If not you would need to compile your own kernel and add the rtc to the devicetree.
On @voodiks LineageOS I have managed it with an extra compiled kernel module and some devicetree commandos.

[mbonamusa]

I'm using the original ubuntu 20.04 image from hardkernel.

[joerg]

Try this commandos:

Code: Select all

sudo modprobe rtc_ds1307
lsmod

When you get this:

Code: Select all

Module                  Size  Used by
rtc_ds1307             40960  0

Then kernel driver is built for your kernel and you have chance to make it work with devicetree changes as this:

Code: Select all

	ds3231: rtc@68 {
		status = "okay";
		compatible = "maxim,ds3231";
		reg = <0x68>;
	};

If you can't do this, or if there is no kernel module, need to ask hardkernel devs, if they can make it for next release.

[mbonamusa]

mbc@c4147B3:~$ sudo modprobe rtc_ds1307
modprobe: FATAL: Module rtc_ds1307 not found in directory /lib/modules/4.9.241-67

So, I suppose Harkernel has to make it for next release.

[odroid]

We will add the driver to the next kernel update.

BTW, the RTC Shield will be available in few days.

[mbonamusa]

Thank you @odroid!

[joerg]

Several different RTC chipset drivers were added with 4.9.241-113 release.
https://github.com/hardkernel/linux/com ... 66004fe0ea